This invention relates to a reed valve arrangement and relates especially to a piston and cylinder gas compressor with a reed valve via which gas is drawn during induction strokes.
Piston and cylinder gas compressors have been proposed during the past two decades which include a valve plate located between a cylinder and a cylinder head, the valve plate providing lower and upper surfaces with which springy flat valve reeds are cooperable alternately to close off induction and delivery apertures respectively. Such valve reeds are typically deflectably mounted only at one end so as to be naturally moveable under the influence of gas pressure created by piston movement. Whilst a delivery reed valve is typically mounted at one end and beneath a suitable arrester, on the upper surface of the valve plate, an induction reed is typically clamped at one end between valve plate and cylinder, a free end being constrained by a stop against excessive downward movement away from the valve plate.
A shortcoming of a compressor employing such an induction reed can be attributed to the stiffness of the clamped reed which results in delay in onset of free air delivery to the compressor during an induction stroke. Such delay can be shortened by making the valve reed somewhat thinner and therefore more flexible to permit earlier resilient flexing at the clamped end. However this does not remove the stress at the clamped end whereas it can result in delay in induction valve closure during the subsequent compression or delivery stroke with attendant limitations of compressor performance.
According to the present invention there is provided a reed valve arrangement comprising a naturally flat springy bendable reed having end regions tiltably supported to hold an intermediate region in closing proximity with at least one aperture of a valve plate surface whilst permitting deflection and bending of said intermediate region without bending of the end regions.
According to the present invention there is more particularly provided a piston and cylinder compressor including a valve plate located between the cylinder and a cylinder head said valve plate having induction and delivery passages with respective valve means, the induction valve means comprising a naturally flat springy reed having end regions and an intermediate region extending across the cylinder to cover the induction passage said end regions being tiltably supported between the cylinder and the valve plate to hold the intermediate region in closing relationship with said induction passage whilst permitting deflection and bending of the intermediate region without bending stress of the end regions.
In order that the invention may be more clearly understood and readily carried into effect the same will be further described by way of example with reference to the accompanying drawings: